81422208 has 192 divisors, whose sum is σ = 280051200. Its totient is φ = 22201344.

The previous prime is 81422207. The next prime is 81422291. The reversal of 81422208 is 80222418.

It is a tau number, because it is divible by the number of its divisors (192).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81422207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 185253 + ... + 185691.

It is an arithmetic number, because the mean of its divisors is an integer number (1458600).

Almost surely, 2^81422208 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81422208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140025600).

81422208 is an abundant number, since it is smaller than the sum of its proper divisors (198628992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81422208 is a wasteful number, since it uses less digits than its factorization.

81422208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 489 (or 474 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 81422208 is about 9023.4255136284. The cubic root of 81422208 is about 433.4253332606.

The spelling of 81422208 in words is "eighty-one million, four hundred twenty-two thousand, two hundred eight".